연약지반 성토시 사면의 안정에 미치는 Geotextile의 효과

김수일,조삼덕,우제윤 연세대학교 산업기술연구소 1982 논문집 Vol.14 No.2

Geotextiles have been extensively used in road constructions as effective and economical materials performing several functions such as separation, filtration, drainage, protection against frost break, and as reinforcement to improve the load bearing capacity and stability of road. In this study, a method for the analysis of embankment reinforced with geotextile is studied. Computer program based on the simplified Bishop method is modified in order to investigate quantitively the effect of gotextile on the slope stability of embankment on weak soils. Evaluation of the tensile strength required for the design safety factor is also possible utilizing the computer program in this study.

열하중을 받는 복합재료 적층판의 손상에 대한 열-음향방출해석

김영복,민대홍,이덕보,최낙삼 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.3

열-음향방출(thermo-AE) 기법을 이용하여 두께 3㎜, [+456/-456]S 복합재료 적층판의 열응력 유기 손상에 대해 비파괴평가의 유효성을 연구하였다. 반복적인 열부하 사이클에 의해서 thermo-AE 사상수가 감소하는 경향이 뚜렷하게 나타나서 열부하에 따른 카이저효과가 관찰되었다. 열부하사이클중의 thermo-AE 거동을 분석하여 복합재료의 응력자유온도를 결정할 수 있었다. 초음파 C스캔, 광학현미경, 주사형 전자현미경을 통해 섬유파단과 모재파손이 관찰되었으며, 이들 파손 인자는 thermo-AE 신호의 단시간 퓨리에 변환처리에 의해 생성된 3종류의 서로 다른 시간-주파수 특성과 대응하였다. 이 특성을 이용하여 복합재료의 냉각열처리 및 반복 열부하사이클시의 손상발생과정 및 내부 마찰 거동 내역을 추적할 수 있었다.

동일한 국제예후지표(International Prognostic Index)를 나타내는 미만성 대형 B-세포 림프종에서 Bcl-2와 p16의 임상적 중요성

박상은,박수진,곽승근,박남숙,천재민,윤환중,조덕연,김삼용,김진만 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

In Korea, malignant lymphoma is a common cancer, comprising about 2.7% of all malignant neoplasm. Diffuse large B cell lymphoma is the most common lymphoma, representing about 50% of all Non-Hodgkin's lymphoma. Diffuse large B-cell lymphoma is usually considered as heterogeneous group of neoplasms rather than a single clinicopathological entity. Clinical prognostic systems, including the International Prognostic Index (IPI), although useful to assess overall prognosis, embrace patients with heterogeneous prognoses. But International Prognostic Index scoring system is not sufficiently predict the prognosis. It is likely that the prognostic assessment of patients with diffuse large B-cell lymphomamight be improved by using biological features. Bcl-2 protein and p16 protein expression is recognized as useful biologic markers predicting the prognosis of patients with diffuse large B-cell lymphoma. To determine the clinical significance and prognostic value of bcl-2 and p16 proteins expression patterns, we studied 18 patients with de novo DLBL, whose archival pathology specimen were available for immunohistochemistry studies, atChungnam National University Hospital from September 1992 to December 2000. Archival specimens from each patient were immunostained with respective antibodies for bcl-2, p16. The results are as follows; 1) The median age was 54(rage : 37-69). There were 12 male patients(66.7%) and 6 female patients(33.3%) The 'B' symptom was abscentin all patients. The stages were as follows : Ⅰ, 2 patient(11.1%), Ⅱ, 10 patient(55.6%), Ⅲ, 4patient(22.2%) and Ⅳ, 2patient(11.1%). 3 patients(16.8%) had the elevated LDH level, 14 patients(77.8%) had the normal LDH level and 1 patients(5.6%) was not identified the LDH level. 2 patients(11.1%) had the bulky disease and 16 patients(88.7%) had no bulky diease. The distribution of ECOG status were O, 2 patients(11.1%c), 1, 14patients(77.8%) and 2, 2patients(11.1%). 2) Theimmunohistochemistry results are as follows bcl-2:+,10 patients(55.6%), bcl-2:-, 8patinets(44.4%), p16:+,3 patients(16.7%), p16:-, 15patients(83.3%) 3) After a median follow UP durations of 67 months, the median survival time was 57 months with a rage of 7-100+ months. 5-years overall survival rates was 44% by Kaplan-Meier method. 4) Reduced overall survival was demonstrated in the patients who expressed bcl-2 protein(P=0.0174). 5-year overall survivial rate was 12%(bcl-2 expression) versus 88%(no bcl-2 expression) 5) Among diffuse large B-cell lymphoma patients with IPI score 0-1, reduced overall survival was demonstrated with bcl-2 expression(P=0.023). 5-year overall survival rate was 18%(bcl-2 expression group) versus 100%(no bcl-2 expressiongroup) 6) Median survival durtation of diffuse large B-cell lymphoma patients negative for p16 expression was 57 months whereas p16 postive patients' median survival duration was not reached(P=0.4478). In diffuse large B-cell lymphoma patients with identical IPI scores, bcl-2 expression had additional prognostic value.

Experimental Investigation of Installation Damage of Geogrids(pp.9-15)

Cho Sam-Deok(조삼덕),Lee Kwang-Wu(이광우),Oh Se-Yong(오세용) 한국토목섬유학회 2004 한국지반신소재학회 논문집 Vol.3 No.3

Water tube를 이용한 가물막이공법 적용성에 관한 연구

조삼덕(Sam-Deok Cho),김주형(Ju-Hyeng Kim),채종길(Jong-Gil Chae),오준영(Jun-Yeong Oh) 한국토목섬유학회 2010 한국지반신소재학회 학술발표회 Vol.2010 No.4

Much damage has been caused and many lives have been lost by floods in annual summer season. The most conventional coffering method is to stack sandbags which have been used for temporary flood protection in most flooding areas. In addition Geotextile tube (geotube) has been applied in 21st Century. However the present temporary coffering methods are labor-intensive, time-consuming, and environmentally-unfriendly. Accordingly a water-filled tube(water tube) dam has been developed recently in foreign countries and applied actively. In contrast of the present methods it can be installed in a very short time and by a small number of people, and it also can be withdrawn easily without unpleasant aftermath. In addition, the filling material, water, is very accessible, especially in an area where flooding is expected, and the tubes can be used repeatedly. Despite of usefulness of water tube system, it is not nearly acceptable in our country and also production and application technique has been not systematized. In this paper, therefore, technical notice and the numerical analysis in application of the water tube method is discussed in detail.

Experimental Investigation of Installation Damage of Geogrids(pp.47-53)

Cho Sam-Deok(조삼덕),Lee Kwang-Wu(이광우),Oh Se-Yong(오세용) 한국토목섬유학회 2004 한국토목섬유학회지 Vol.3 No.3

국내 블록식 보강토옹벽의 개선방안 및 전망(pp.43-53)

조삼덕(Sam-Deok Cho) 한국토목섬유학회 2001 한국토목섬유학회 학술발표회 Vol.2001 No.4

2단 고성토 보강토옹벽의 거동평가 - 사례연구

조삼덕(Sam-Deok Cho),이광우(Kwang-Wu Lee),이훈연(Hoon-Yeon Lee),장기수(Ki-Soo Chang) 한국토목섬유학회 2005 한국지반신소재학회 학술발표회 Vol.2005 No.12

토목섬유 보강재에 적용한 스트레인게이지 실측값의 신뢰성 평가

조삼덕(Sam-Deok Cho),이광우(Kwang-Wu Lee),Zhuang Li,김욱기(Uk-Gie Kim) 한국지반신소재학회 2015 한국지반신소재학회 논문집 Vol.14 No.4

토목섬유(Geosynthetics)는 도로, 철도, 항만, 댐, 제방 등의 각종 토목구조물에 보강, 배수, 필터, 분리, 침식방지 등의 용도로 폭넓게 적용되고 있다. 특히 토목섬유는 보강토옹벽이나 사면/지반 보강 등을 위한 보강용도로서의 적용이 활발하며, 최근에는 성토체의 안정성과 시공성 및 경제성 향상을 도모하기 위해 성토지지말뚝 상부를 토목섬유로 보강하는 기법에 대한 연구가 진행되고 있다. 일반적으로 토목섬유 보강재를 사용한 토목구조물의 안정성 해석을 위하여 실내 모형실험이나 현장에 적용된 토목섬유에 스트레인게이지를 부착하여 토목섬유의 인장변형을 측정하는 방법을 사용하고 있다. 그러나, 토목섬유의 제조방법과 강성도 및 스트레인게이지 부착방법 등에 따라 측정된 인장변형률 값의 편차가 나타난다. 본 연구에서는 지오그리드와 직포, 부직포 등 3가지 형태의 토목섬유를 대상으로 스트레인게이지가 부착된 토목섬유에 대한 광폭인장강도시험을 수행하여 video extensometer를 이용하여 측정된 인장변위로부터 산정한 인장변형률과 스트레인게이지에 의해 측정된 인장변형률을 비교, 분석함으로써 스트레인게이지 실측값의 신뢰성을 평가하였다. 분석 결과, 스트레인게이지 실측값은 비교적 강성이 높은 지오그리드와 직포의 경우에는 신뢰도가 높으나, 강성이 작은 부직포의 경우에는 신뢰도가 매우 낮음을 알 수 있었다. Geosynthetics are widely used in different ways such as reinforcement of structures in road, railway, harbor and dam engineering, drainage, separation and erosion prevention. They are especially applied to reinforced retaining wall and slope or ground reinforcement. Recently, geosynthetics reinforced pile supported (GRPS) embankment was developed to improve stability and construability of embankments in railway engineering. Extension strains are usually measured by strain gauges adhered to geosynthetics to evaluate the stability of geosynthetics. However, the measurements are influenced by manufacturing method and stiffness of geosynthetics and also adherence of strain gauge. In this study, wide-width tensile strength tests were performed on three types of geosynthetics including geogrid, woven geotextile and non-woven geotextile. During the test, strains of geosynthetics were measured by both video extensometer and strain gauges adhered to the geosynthetics and the measured results were compared. Results show that the measured results by strain gauges have high reliability in case of large stiffness geosythetics like geogrid and woven geotextile, whereas they have very low reliability for small stiffness geosythetics like non-woven geotextile.

국내 블록식 보강토옹벽의 개선방안 및 전망(pp.3-13)

조삼덕(Sam-Deok Cho) 한국토목섬유학회 2007 한국토목섬유학회 학술발표회 Vol.2007 No.4

Block-type reinforced earth walls have been increasingly used in Korea since 1995. However, many reported cases of failed block-type reinforced earth walls construction indicates that civil engineers of Korea are still not fully aware of design and construction technology of block-type reinforced earth walls, and also that we have not made enough investment for the development of block-type reinforced earth walls technology. In order to improve the current domestic block-type reinforced earth walls technology and to increase its application in Korea, this paper examines many technological problems, revealed from past construction cases, and discusses how to improve block-type reinforced earth walls technology in terms of design, construction, maintenance, and material, and also its prospect.